The galactic wind in the circum-nuclear zone of NGC 6946

Beckman, J. E.; Munoz-Tunon, C.; Prieto, M.; Battaner, E.; Sanchez Saavedra, M. L.
Bibliographical reference

Astronomy and Astrophysics (ISSN 0004-6361), vol. 161, no. 1, June 1986, p. 55-60.

Advertised on:
6
1986
Number of authors
5
IAC number of authors
2
Citations
13
Refereed citations
11
Description
Using the H-II region H-alpha emission detected in high-resolution long slit spectra of the normal spiral NGC 6946 out to 6 kpc from the center, and along 8 radii equally spaced in angle, velocity curves of the circumnuclear zone are obtained. The curves show that the radial velocity gradient, and the limiting radial velocity along the minor axis are much greater than those along the major axis, in contrast to models in which rotational velocities predominate. The present results and previous observations of CO suggest that the central gas of NGC 6946 is in a state of expansion, with the driving force for this expansion coming from the 10,000 O5 stars known to be present within the disk component of the zone. Both the supernovae model and the model with radiative coupling to the gas via the copious dust are found to satisfy the energy and momentum requirements, and both may be operating to drive the observed wind.